Method, device and equipment for adjusting primary mirror and secondary mirror of off-axis reflection system and storage medium

Abstract

The invention discloses an off-axis reflection system primary and secondary mirror installation and adjustment method, device and equipment and a storage medium, and the method comprises the steps: placing a primary mirror in a detection light path according to the position setting of an interferometer and a first hologram detection tool, and carrying out the position determination; according to a position determination result, a second hologram gauge is placed in the detection light path so that the positioning reference of the second hologram gauge and the positioning reference of the primary mirror can be kept consistent; and positioning the secondary mirror by using a second hologram gauge, and adjusting the position and posture of the secondary mirror by detecting the light path, so that the positions of the secondary mirror and the primary mirror meet the requirements. The objective of the invention is to solve the technical problems in the prior art that the cost is high, errors are easy to accumulate in the installation and adjustment process, the installation and adjustment effect is poor and the installation and adjustment period is affected because the installation and adjustment of the primary and secondary mirrors need a compensator, and the CGH technology is used to reduce the processing and manufacturing cost of the compensator and improve the detection and alignment precision, the whole process is simple to operate, and the installation and adjustment period is improved.

Description

Technical Field

[0001] The present application relates to the field of optical alignment and detection, and in particular to a method, device, equipment and storage medium for aligning primary and secondary mirrors of an off-axis reflection system. Background Art

[0002] At present, the structural forms of optical systems include refractive, reflective and catadioptric. Since the refractive optical system will produce chromatic aberration, it is difficult to completely correct it, and it requires many components, making it difficult to achieve lightweight design. Therefore, the reflective system is the mainstream solution for the current space camera design. Among them, the reflective system (Ritchey-Chrétien, RC) is widely used in aerospace and other fields due to its large aperture, long focal length, wide spectrum, and easy lightweight. With the continuous development of optical technology, the imaging requirements for space cameras are also constantly increasing. Small aberrations, large fields of view, compact structures, and other special design requirements have posed higher challenges to the design and assembly of optical systems. Off-axis reflective systems and offset reflective systems have attracted much attention because they can meet these design requirements, but their assembly and adjustment are much more difficult than coaxial systems.

[0003] For the coaxial primary and secondary mirror system, the adjustment process is relatively simple and efficient. The interferometer can be used directly to detect the wavefront aberration of the system, and then the adjustment can be performed according to the aberration characteristics of the system. However, for the off-axis RC system, since there is an angle between the optical axes of the primary and secondary mirrors, and the primary and secondary mirror system is not a perfect imaging, it is difficult to perform adjustment directly through interferometer detection. This not only makes it difficult to ensure that the optical axis is adjusted to the designed state, but also accumulates more errors due to the complexity of the system itself. Summary of the invention

[0004] The main purpose of the present application is to provide a method, device, equipment and storage medium for assembling the primary and secondary mirrors of an off-axis reflection system, aiming to solve the technical problems in the prior art that the primary and secondary mirrors of an off-axis reflection system require a compensator for adjustment, which results in high cost, easy accumulation of errors during the adjustment process, poor adjustment effect and a shortened adjustment cycle. Compared with traditional compensators, the compensator is manufactured using computer-generated hologram (CGH) technology, which reduces the processing and manufacturing cost of the compensator, improves the detection and alignment accuracy, makes the whole process simple to operate and shortens the adjustment cycle.

[0005] To achieve the above-mentioned purpose, the present application provides a method for assembling and adjusting primary and secondary mirrors of an off-axis reflection system, and the method for assembling and adjusting primary and secondary mirrors of an off-axis reflection system comprises:

[0006] According to the settings of the interferometer and the first hologram inspection fixture, the primary mirror is placed in the detection light path and the position is determined;

[0007] According to the result of the position determination, placing a second hologram inspection fixture in the detection light path so that the second hologram inspection fixture is consistent with the positioning reference of the primary mirror;

[0008] The secondary mirror is positioned by using the second hologram inspection fixture, and the position and posture of the secondary mirror are adjusted through the detection optical path so that the positions of the secondary mirror and the primary mirror meet the requirements.

[0009] In one embodiment, before the step of placing the primary mirror in the detection light path and determining the position according to the setting of the interferometer and the first hologram inspection fixture position, the step includes:

[0010] Installing a standard spherical lens matching the first hologram inspection fixture on the interferometer;

[0011] The spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​the first hologram tester, and the first hologram tester is adjusted so that the interference fringes generated in the interferometer alignment area of ​​the first hologram tester reach a zero fringe state.

[0012] In one embodiment, the step of placing the primary mirror in the detection light path and determining the position according to the settings of the interferometer and the first hologram inspection fixture comprises:

[0013] Keeping the positions of the interferometer and the first hologram inspection fixture unchanged, placing the primary mirror in the detection light path;

[0014] The primary mirror detection area of ​​the first hologram inspection fixture emits a wavefront that matches the surface phase of the primary mirror, which is incident on the primary mirror and then reflected back to the interferometer by the surface of the primary mirror to generate interference fringes;

[0015] The surface shape of the primary mirror is subjected to zero position detection, and the inclination and translation of the primary mirror are adjusted according to the detection result to determine the positional relationship between the primary mirror and the first hologram inspection fixture.

[0016] In one embodiment, the step of placing the second hologram checker in the detection light path according to the result of the position determination so that the second hologram checker is consistent with the positioning reference of the primary mirror comprises:

[0017] The second hologram gauge is placed in the detection optical path, and the light emitted from the second hologram gauge alignment area on the first hologram gauge is incident on the first hologram gauge alignment area on the second hologram gauge, and returns to the interferometer along the original path through the second hologram gauge to generate the interference fringes;

[0018] Finely adjusting the position of the second hologram inspection fixture so that the interference fringes reach a zero-fringe state;

[0019] The positioning references of the second hologram inspection fixture and the primary mirror are made consistent.

[0020] In one embodiment, before the step of positioning the secondary mirror using the second hologram inspection fixture and adjusting the position and posture of the secondary mirror through the detection optical path so that the position of the secondary mirror and the primary mirror reaches the required position, the step includes:

[0021] Adjusting the position of the interferometer and moving the interferometer behind the position of the primary mirror;

[0022] Mounting a standard spherical lens matching the second hologram inspection fixture on the interferometer so that the spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​the second hologram inspection fixture;

[0023] The interferometer is adjusted so that the interference fringes generated by the interferometer aiming area reach a zero fringe state.

[0024] In one embodiment, the step of positioning the secondary mirror by using the second hologram inspection fixture, and adjusting the position and posture of the secondary mirror by using the detection optical path so that the position of the secondary mirror and the primary mirror meet the requirements includes:

[0025] Keeping the position of the interferometer unchanged, placing the secondary mirror in the detection light path;

[0026] The wavefront emitted from the secondary mirror detection area in the second hologram inspection fixture and matching the surface phase of the secondary mirror is incident on the secondary mirror, and then reflected back to the interferometer by the surface of the secondary mirror to generate the interference fringes;

[0027] Performing zero position detection on the surface shape of the secondary mirror, and adjusting the inclination and translation of the secondary mirror according to the detection result to determine the positional relationship between the secondary mirror and the second hologram inspection fixture;

[0028] The positional relationship between the secondary mirror and the primary mirror is determined according to the positional relationship between the secondary mirror and the second hologram gauge.

[0029] In one embodiment, the step of installing a standard spherical lens matching the first hologram inspection fixture on the interferometer further includes:

[0030] Detecting the working state of the interferometer;

[0031] When the working state of the interferometer is in a working state without fault indication, the step of installing the standard spherical lens matched with the first hologram gauge on the interferometer is performed.

[0032] In addition, to achieve the above-mentioned purpose, the present application also proposes a primary and secondary mirror adjustment device for an off-axis reflection system, the primary and secondary mirror adjustment device for an off-axis reflection system comprising: a primary mirror determination module, a second hologram inspection fixture determination module and a secondary mirror determination module;

[0033] The primary mirror determination module places the primary mirror in the detection light path and determines the position according to the settings of the interferometer and the first hologram inspection fixture;

[0034] The second hologram fixture determination module places the second hologram fixture in the detection light path according to the position determination result so that the second hologram fixture is consistent with the positioning reference of the primary mirror;

[0035] The secondary mirror determination module uses the second hologram inspection fixture to position the secondary mirror, and adjusts the position and posture of the secondary mirror through the detection optical path so that the positions of the secondary mirror and the primary mirror meet the requirements.

[0036] In addition, to achieve the above-mentioned purpose, the present application also proposes a device for assembling and adjusting primary and secondary mirrors of an off-axis reflection system, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the method for assembling and adjusting primary and secondary mirrors of an off-axis reflection system as described above.

[0037] In addition, to achieve the above-mentioned purpose, the present application also proposes a computer storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method for adjusting the primary and secondary mirrors of the off-axis reflection system as described above are implemented.

[0038] The present application relates to the adjustment of primary and secondary mirrors in an off-axis reflection system, and specifically to an adjustment method for off-axis primary and secondary mirrors in which the optical axes of the primary and secondary mirrors have an angle and non-ideal imaging, in order to solve the problem that the adjustment of the primary and secondary mirrors in the off-axis reflection system in the prior art requires the manufacture of a compensator, which increases the cost and easily accumulates errors during the adjustment process, resulting in poor adjustment effect and affecting the adjustment cycle. The present application is based on the adjustment method for the primary and secondary mirrors in an off-axis reflection system, by setting a first hologram gauge and a second hologram gauge, forming an alignment optical path and a detection optical path, transferring the primary mirror reference to the first hologram gauge, and then determining the position of the second hologram gauge by the first hologram gauge, and finally using the second hologram gauge to determine the secondary mirror, and completing the determination of the relative positions of the primary and secondary mirrors, because CGH can theoretically design arbitrary wavefronts through algorithms on a computer, the design error is very small, and the alignment operation through the designed alignment area is simple and easy, the error accumulation of the entire reference transfer process is small, and the high-precision adjustment and positioning of the primary and secondary mirrors can be achieved efficiently and quickly. The various components are positioned by relying on the designed CGH, and the reference is transferred through the CGH, so that the positions of the primary and secondary mirrors are determined on the same reference, thereby realizing the determination of the relative positions of the primary and secondary mirrors. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0040] Figure 1 It is a first structural schematic diagram of the primary and secondary mirror adjustment device of the off-axis reflection system involved in the embodiment of the present application;

[0041] Figure 2 It is a second structural schematic diagram of the primary and secondary mirror adjustment device of the off-axis reflection system involved in the embodiment of the present application;

[0042] Figure 3 This is a schematic flow chart of a first embodiment of a method for assembling and adjusting primary and secondary mirrors of an off-axis reflection system of the present application;

[0043] Figure 4 This is a flow chart of a second embodiment of the method for assembling and adjusting primary and secondary mirrors of an off-axis reflection system of the present application;

[0044] Figure 5 This is a schematic flow chart of a third embodiment of a method for assembling and adjusting primary and secondary mirrors of an off-axis reflection system of the present application.

[0045] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0047] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0048] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0049] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0050] CGH (Computer-Generated Hologram) is an advanced technology that uses computer technology to simulate the interference and diffraction process of light to generate hologram data. CGH technology generates holograms by calculating and simulating the wave behavior of light based on the principles of interference and diffraction of light. In the computer, the light intensity and phase information of each point on the hologram are designed and calculated by algorithms, which can accurately reproduce the three-dimensional light field of the object. CGH technology can generate high-precision holograms, and its resolution and accuracy depend on the computing power of the computer and the degree of optimization of the algorithm. Since CGH technology is calculated and designed on the computer, it can flexibly generate holograms of various shapes, sizes and complexities. The generated holograms can be edited and modified on the computer to meet different application requirements. The holograms generated by CGH technology exist in digital form, which is convenient for storage, transmission and processing.

[0051] Using CGH technology, arbitrary wavefronts can be designed by algorithms on computers with very small design errors. It can accurately transmit and detect information about the light wavefront, providing a reliable benchmark for adjustment. This off-axis primary and secondary mirror adjustment method mainly relies on the designed computer-generated hologram to locate each component, and uses CGH to transfer the benchmark, so that the positions of the primary and secondary mirrors are determined on the same benchmark, thereby achieving the determination of the relative positions of the primary and secondary mirrors. This method combines the high-precision detection capability of the interferometer and the flexible design of CGH to achieve efficient and high-precision adjustment.

[0052] The detection optical path includes: an optical interferometer (1), CGH1 (2), a primary mirror (3), CGH2 (4), and a secondary mirror (5), wherein:

[0053] The CGH1 is designed with an interferometer alignment area, a CGH2 alignment area, and a primary mirror detection area;

[0054] The CGH2 design includes an interferometer alignment area, a CGH1 alignment area, and a secondary mirror detection area.

[0055] Construction of alignment optical path and detection optical path: By setting the first hologram test fixture CGH1 and the second hologram test fixture CGH2, the alignment optical path and the detection optical path are constructed. Figure 1 As shown, Figure 1 1 is a schematic diagram of the first structure of the primary and secondary mirror adjustment device of the off-axis reflection system involved in the embodiment of the present application, and CGH2 is placed in the detection light path. First, the primary mirror reference is transmitted to CGH1, and then the position of CGH2 is determined by CGH1. Figure 2 As shown, Figure 2 This is the second structural schematic diagram of the primary and secondary mirror adjustment equipment of the off-axis reflection system involved in the embodiment of the present application. The secondary mirror is placed in the detection light path, and the secondary mirror detection area in CGH2 emits a wavefront that matches the phase of the secondary mirror surface and is incident on the secondary mirror, and then is reflected back to the interferometer by the secondary mirror surface along the original path. Finally, CGH2 is used to determine the position of the secondary mirror, thereby completing the determination of the relative positions of the primary and secondary mirrors. Since the alignment area designed by CGH is simple and easy to operate, and the error accumulation of the entire reference transfer process is small, it is possible to achieve efficient, fast, and high-precision adjustment and positioning of the primary and secondary mirrors.

[0056] The present application provides a method for adjusting the primary and secondary mirrors of an off-axis reflection system, referring to Figure 3 , Figure 3 This is a schematic flow chart of the first embodiment of the method for assembling and adjusting the primary and secondary mirrors of the off-axis reflection system of the present application.

[0057] In this embodiment, the method for assembling and adjusting the primary and secondary mirrors of the off-axis reflection system comprises the following steps:

[0058] Step S10: placing the primary mirror in the detection light path and determining the position according to the settings of the interferometer and the first hologram inspection fixture;

[0059] Step S20: according to the result of the position determination, placing the second hologram inspection fixture in the detection light path so that the positioning reference of the second hologram inspection fixture and the primary mirror are consistent;

[0060] Step S30: using the second hologram inspection fixture to position the secondary mirror, and adjusting the position and posture of the secondary mirror through the detection optical path so that the positions of the secondary mirror and the primary mirror meet the requirements.

[0061] Specifically, in this embodiment, the off-axis primary and secondary mirror adjustment method relies on a high-precision interferometer and a specially designed CGH to achieve reference transfer and component positioning. The process includes three main steps: positioning of the primary mirror, placement of the second hologram checker (CGH2) and consistency with the positioning reference, and positioning and adjustment of the secondary mirror. The following is a detailed description of the above steps:

[0062] Step S10: The preparation work needs to ensure that the required equipment such as the interferometer, CGH1, and standard spherical lens are complete and in good working condition. At the same time, it is required to operate in a constant temperature, constant humidity, and vibration-free environment to reduce the influence of external factors on the installation accuracy. The standard spherical lens matching the designed CGH1 is installed on the interferometer. The spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​​​CGH1. By adjusting the position and posture of CGH1, the interference fringes generated in the interferometer alignment area reach the zero fringe state. This step ensures the precise alignment between the interferometer and CGH1. After confirming that the interferometer and CGH1 are aligned correctly, the primary mirror is placed in the detection optical path. The wavefront emitted from the primary mirror detection area in CGH1 that matches the phase of the primary mirror surface is incident on the primary mirror, and then reflected back to the interferometer by the original path of the primary mirror surface to generate interference fringes. Through the observation and analysis of the interference fringes, the zero position detection of the primary mirror surface shape is performed. According to the detection results of the primary mirror surface shape, the tilt and translation of the primary mirror are adjusted to minimize aberrations such as power (astigmatism), coma, and spherical aberration. When these aberrations are adjusted to a minimum, the positional relationship between the primary mirror and CGH1 is determined.

[0063] Step S20: Preparation and placement of CGH2, ensuring that CGH2 is designed with an interferometer alignment area, a CGH1 alignment area, and a secondary mirror detection area. Place CGH2 in the detection optical path, ensuring that the optical path between it, CGH1, and the interferometer is unobstructed. The light emitted from the CGH2 alignment area on CGH1 is incident on the CGH1 alignment area on CGH2. By adjusting the position and posture of CGH2, the interference fringes generated by the light reflected back to the interferometer by CGH2 reach a zero-fringe state. When the interference fringes reach a zero-fringe state, it indicates that the positional relationship between CGH2 and CGH1 has been determined. Since the positional relationship between CGH1 and the primary mirror is known, the positioning reference of CGH2 and the primary mirror is consistent at this time.

[0064] Step S30: Movement of interferometer and replacement of standard spherical lens. Move the interferometer behind the primary mirror to ensure that the optical path between it and CGH2 is unobstructed. Install the standard spherical lens that matches the designed CGH2 on the interferometer. The spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​CGH2. By adjusting the position and posture of the interferometer (or fine-tuning the position of CGH2, if necessary), the interference fringes generated in the interferometer alignment area reach a zero-fringe state.

[0065] After confirming that the interferometer and CGH2 are aligned correctly, place the secondary mirror in the detection light path. The wavefront emitted from the secondary mirror detection area in CGH2 and matching the phase of the secondary mirror surface is incident on the secondary mirror, and then reflected back to the interferometer by the secondary mirror surface to generate interference fringes. The zero position detection of the secondary mirror surface shape is performed through the observation and analysis of the interference fringes. According to the detection results of the secondary mirror surface shape, the tilt and translation of the secondary mirror are adjusted to minimize aberrations such as power (astigmatism), coma, and spherical aberration. This step requires fine adjustment to ensure that the relative position relationship between the secondary mirror and the primary mirror meets the design requirements. Finally, it is confirmed that when the aberration of the secondary mirror is adjusted to the minimum, the position relationship between the secondary mirror and CGH2 (and the primary mirror) is determined. At this point, the entire off-axis primary and secondary mirror adjustment process is completed.

[0066] It is particularly important to note that, through the detailed description of the above steps, it can be seen that the off-axis primary and secondary mirror adjustment is a complex and delicate process. It relies on high-precision interferometers and specially designed CGHs to achieve reference transfer and component positioning. In each step, precise alignment, detection and adjustment are required to ensure the imaging quality and performance of the system. In actual operation, the following points should also be noted:

[0067] Environmental control: Ensure operation in a constant temperature, constant humidity, and vibration-free environment to reduce the impact of external factors on installation and adjustment accuracy.

[0068] Equipment calibration: Regularly calibrate and maintain interferometers, CGH and other equipment to ensure their accuracy and stability.

[0069] Data recording: Record relevant data (such as interference fringe patterns, adjustment parameters, etc.) in each step of the operation for subsequent analysis and optimization.

[0070] Furthermore, in this embodiment, before the step of placing the primary mirror in the detection light path and determining the position according to the setting of the positions of the interferometer and the first hologram inspection fixture, the method further comprises:

[0071] Installing a standard spherical lens matching the first hologram inspection fixture on the interferometer;

[0072] The spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​the first hologram tester, and the first hologram tester is adjusted so that the interference fringes generated in the interferometer alignment area of ​​the first hologram tester reach a zero fringe state.

[0073] Specifically, in this embodiment, the core of the off-axis primary and secondary mirror adjustment method is to use the interferometer and CGH to achieve high-precision reference transfer and component positioning. Before placing the primary mirror in the detection light path, a series of preparations need to be completed, including the installation of the standard spherical lens, the alignment of the interferometer and CGH1, etc. These steps lay a solid foundation for the subsequent adjustment process. The following is a detailed description of the above steps:

[0074] Select a standard spherical lens that matches the CGH1 design. This lens should have a curvature and precision that matches the alignment area of ​​the CGH1 interferometer. Before installation, carefully inspect the standard spherical lens to ensure that its surface is free of scratches, contamination, and that the optical performance is good. Ensure that the interferometer mounting bracket is stable and can accurately adjust the position and attitude of the lens. Install the standard spherical lens to the interferometer mounting bracket to ensure that the lens is aligned with the optical axis of the interferometer. By fine-tuning the adjustment mechanism on the mounting bracket, preliminarily adjust the position and attitude of the lens to roughly meet the alignment requirements. After the lens is installed, start the interferometer and calibrate it to ensure the measurement accuracy and stability of the interferometer. Using the interferometer's fine-tuning mechanism, accurately adjust the position of the lens so that it is completely aligned with the interferometer's optical axis. By adjusting the lens's attitude (such as tilt and rotation), ensure that the surface of the lens is parallel to the interferometer's measurement plane. After ensuring that all equipment is connected correctly and stably, start the interferometer. According to the design parameters of CGH1 and the performance requirements of the interferometer, configure the interferometer's measurement parameters, such as wavelength, measurement range, etc. The spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​CGH1. This spherical wave should have a wavelength and curvature that matches the design of CGH1. Interference fringe observation, after the spherical wave is incident on CGH1, the interference fringes are observed using the observation system of the interferometer. These interference fringes reflect the phase difference between the spherical wave and the surface of CGH1.

[0075] According to the observed interference fringes, the position and attitude of CGH1 are adjusted. This adjustment process requires precision and patience, because even a small change in position can lead to significant changes in the interference fringes. By analyzing the shape, number and distribution of the interference fringes, the phase difference between CGH1 and the interferometer alignment area can be determined. According to the analysis results, the position and attitude of CGH1 are gradually adjusted to gradually reduce the interference fringes and tend to the zero fringe state. During the adjustment process, the changes in the interference fringes are continuously observed to ensure that the zero fringe state is achieved throughout the CGH1 interferometer alignment area.

[0076] During the entire assembly process, ensure that the working environment has a constant temperature and humidity. This helps reduce the impact of thermal expansion and humidity changes on the assembly accuracy. Ensure that the working environment is free of shock or vibration. Vibration may cause fluctuations and instability in the interference fringes, affecting the assembly accuracy.

[0077] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be described in detail later. Figure 4 , Figure 4 The flowchart of the second embodiment of the method for adjusting the primary and secondary mirrors of the off-axis reflection system of the present application is shown in step S10. The step of placing the primary mirror in the detection light path and determining the position according to the setting of the interferometer and the first hologram inspection fixture position includes:

[0078] Step S11: keeping the positions of the interferometer and the first hologram inspection fixture unchanged, and placing the primary mirror in the detection light path;

[0079] Step S12: The primary mirror detection area of ​​the first hologram inspection fixture emits a wavefront that matches the surface phase of the primary mirror and is incident on the primary mirror, and then is reflected back to the interferometer by the surface of the primary mirror to generate interference fringes;

[0080] Step S13: performing zero position detection on the surface shape of the primary mirror, and adjusting the tilt and translation of the primary mirror according to the detection result to determine the positional relationship between the primary mirror and the first hologram inspection fixture.

[0081] In this embodiment, the complete steps of placing the primary mirror in the detection light path and determining the position according to the position setting of the interferometer and the first hologram inspection fixture are described in detail, including the specific operation, technical details, precautions, and possible problems and solutions for each step. The following is a detailed description of the above steps:

[0082] Step S11: Keep the interferometer and CGH1 unchanged and place the primary mirror in the detection light path. First, ensure that the positions of the interferometer and CGH1 have been accurately calibrated and fixed. Then, use a fine-tuning mechanism or a lifting device to gently place the primary mirror in the detection light path. During the placement process, be careful to avoid collision between the primary mirror and the interferometer or CGH1. Ensure that the position of the primary mirror is roughly aligned with the reference of the interferometer and CGH1.

[0083] Note: When placing the primary mirror, be careful to avoid damage to it. Make sure the support structure of the primary mirror is stable and reliable, able to support the weight of the primary mirror and keep its position stable.

[0084] After placing the primary mirror in the detection optical path, a preliminary alignment is required to ensure that the relative position of the primary mirror to the interferometer and CGH1 is approximately correct. Observe the generation of interference fringes. If the interference fringes are unclear or too numerous, it may be due to incorrect relative position between the primary mirror and CGH1. Use the fine adjustment mechanism to adjust the position of the primary mirror to better align it with the optical axis of the interferometer and CGH1. During the adjustment process, proceed step by step and observe the changes in the interference fringes after each adjustment. When adjusting the position of the primary mirror, try to avoid excessive impact or friction on the primary mirror. Ensure the accuracy and stability of the fine adjustment mechanism so that the position of the primary mirror can be accurately adjusted.

[0085] Step S12: The wavefront transmitted through CGH1 is incident on the primary mirror, and then reflected back to the interferometer by the original path of the primary mirror surface to generate interference fringes. After the spherical wave of the interferometer passes through CGH1, a wavefront matching the phase of the primary mirror surface is emitted from CGH1. Observe whether the wavefront is accurately projected onto the primary mirror, and check whether the reflected light from the primary mirror is accurately returned to the interferometer. If the reflected light does not return to the interferometer, it may be caused by incorrect position of the primary mirror. Use the fine-tuning mechanism to adjust the position and attitude of the primary mirror to ensure that the reflected light can accurately return to the interferometer. When adjusting the CGH and the primary mirror, ensure that the relative position relationship between them remains stable. Avoid damage to the primary mirror or CGH during the adjustment process.

[0086] Step S13: Perform zero-position detection on the surface shape of the primary mirror, and adjust the tilt and translation of the primary mirror according to the detection results. In the zero-position detection, the surface phase of the measured element (such as the primary mirror) matches the reference wavefront (such as the wavefront of the CGH test fixture), thereby directly generating interference fringes. The shape, number and distribution of these fringes provide direct information about the accuracy of the surface shape of the primary mirror. The interferometer can obtain the surface shape accuracy described numerically. It is more accurate to evaluate the surface shape of the primary mirror using the interferometer detection results. When making coarse adjustments, the direction of adjustment can be determined based on the fringes.

[0087] Align the primary mirror and make a rough adjustment through the fringes when detecting the surface shape of the primary mirror. According to the test results, it is mainly judged by adjusting the primary mirror until the surface shape result obtained by the test is the best, that is, the aberration is the smallest. When adjusting the tilt and translation of the primary mirror, pay attention to keeping the support structure of the primary mirror stable and reliable. Also avoid excessive impact or friction on the primary mirror during the adjustment process. Ensure the accuracy and stability of the fine-tuning mechanism so that the position and posture of the primary mirror can be accurately adjusted. During the adjustment process, pay close attention to the changes in the interference fringes so as to adjust the adjustment direction and strength in time. After completing all adjustments, make a final evaluation of the surface shape detection results. If the best surface shape detection result of the primary mirror can be detected, it means that the positional relationship between the primary mirror and the CGH has been determined. Use a locking mechanism to fix the position of the primary mirror and the support structure to prevent displacement in subsequent operations.

[0088] Further, in this embodiment, the step of placing the second hologram check fixture in the detection light path according to the result of the position determination so that the second hologram check fixture is consistent with the positioning reference of the primary mirror includes:

[0089] Step S21: the second hologram fixture is placed in the detection optical path, and the light emitted from the second hologram fixture alignment area on the first hologram fixture is incident on the first hologram fixture alignment area on the second hologram fixture, and returns to the interferometer along the original path through the second hologram fixture to generate the interference fringes;

[0090] Step S22: finely adjusting the position of the second hologram inspection fixture so that the interference fringes reach a zero-fringe state;

[0091] Step S23: completing the alignment of the positioning references of the second hologram inspection fixture and the primary mirror.

[0092] In this embodiment, the precise adjustment of the off-axis primary and secondary mirror system is crucial. This complex process requires not only determining the position of the primary mirror, but also accurately placing the second hologram fixture (CGH2) to ensure that it is consistent with the positioning reference of the primary mirror. The following is a detailed description of the above steps:

[0093] Step S21: CGH2 is placed in the detection light path, and the light emitted from the second hologram fixture alignment area on CGH1 is incident on the first hologram fixture alignment area on CGH2. While ensuring that the positions of CGH1 and the primary mirror are stable and accurate, CGH2 is gently placed in the detection light path. Adjust the position and posture of CGH2 so that the first hologram fixture alignment area on it can be aligned with the light emitted from the second hologram fixture alignment area on CGH1. This may require gradual adjustments using a fine-tuning mechanism, while observing the changes in the interference fringes in the interferometer to ensure that the light can accurately be incident on CGH2 and return to the interferometer along the original path. When placing CGH2, be gentle to avoid damage to CGH2. Ensure that the support structure of CGH2 is stable and reliable, and can support the weight of CGH2 and keep its position stable.

[0094] When adjusting the position and posture of CGH2, pay close attention to the changes in the interference fringes so as to adjust the adjustment direction and strength in time. In order to ensure that the light can be accurately incident on CGH2 and return to the interferometer by the original path, the position and posture of CGH2 need to be precisely controlled. This may require the use of high-precision fine-tuning mechanisms and high-resolution measuring equipment. During the adjustment process, the real-time feedback function of the interferometer can be used to observe the number, shape and distribution of interference fringes so as to promptly determine whether the position and posture of CGH2 are accurate. Light incidence and reflection process The light emitted from the second hologram inspection fixture alignment area on CGH1 is transmitted and transformed by a series of optical elements, and finally incident on the first hologram inspection fixture alignment area on CGH2. On CGH2, these lights will be phase modulated according to the design of CGH2 and return to the interferometer by the original path.

[0095] The design of CGH2 is based on the theoretical surface shape of the secondary mirror and its relative position to the primary mirror. When light is incident on CGH2, CGH2 will phase modulate the light according to its design. This phase modulation will cause specific interference fringes to be generated when the light returns to the interferometer. These fringes reflect the relative position between CGH2 and CGH1.

[0096] Step S22: Fine-tune the position of CGH2 so that the interference fringes reach the zero-fringe state. After the initial alignment of CGH2, use the fine-tuning mechanism to fine-tune the position of CGH2. During the adjustment process, pay close attention to the changes in the interference fringes in the interferometer. By gradually adjusting the position and posture of CGH2, the interference fringes are gradually reduced and finally reach the zero-fringe state. The zero-fringe state indicates that the relative position relationship between CGH2 and CGH1 has been accurately matched, that is, the relative position relationship with the primary mirror has also been accurately matched. When fine-tuning the position of CGH2, ensure the accuracy and stability of the fine-tuning mechanism. Avoid causing excessive impact or friction to CGH2 during the adjustment process. During the adjustment process, continue to observe the changes in the interference fringes, and adjust the adjustment direction and strength according to the actual situation. Avoid excessive adjustment that causes the CGH2 position to deviate from the optimal state.

[0097] By analyzing the number, shape, and distribution of interference fringes, you can determine whether the position of CGH2 is accurate and guide the subsequent adjustment direction. In the process of fine-tuning the position of CGH2, it may be necessary to further optimize the interference fringes to achieve the best state. Consider the impact of environmental factors (such as temperature, humidity, vibration, etc.) on the interference fringes, and take appropriate measures to compensate. When optimizing the interference fringes, ensure that all measurements and adjustments are accurate and reliable. Avoid introducing additional errors or uncertainties. Keep an eye on the changes in the interference fringes and adjust and optimize according to the actual situation. Ensure that the final interference fringes are clear, stable, and accurate.

[0098] Step S23: Complete the positioning reference of CGH2 and the primary mirror. Evaluate whether the relative position relationship between CGH2 and the primary mirror meets the design requirements. If the measurement results meet the design requirements, confirm that the positioning reference of CGH2 and the primary mirror are consistent. Note: During the measurement process, ensure the accuracy and stability of the measuring equipment. Avoid introducing additional errors or uncertainties. Carefully analyze and evaluate the measurement results to ensure that the relative position relationship between CGH2 and the primary mirror is accurate and reliable.

[0099] Furthermore, in this embodiment, before the step of positioning the secondary mirror by using the second hologram inspection fixture and adjusting the position and posture of the secondary mirror through the detection optical path so that the position of the secondary mirror and the primary mirror reaches the required level, the step includes:

[0100] Adjusting the position of the interferometer and moving the interferometer behind the position of the primary mirror;

[0101] A standard spherical lens matched with the second hologram inspection fixture is mounted on the interferometer, so that the spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​the second hologram inspection fixture.

[0102] The interferometer is adjusted so that the interference fringes generated by the interferometer aiming area reach a zero fringe state.

[0103] In this embodiment, the positioning and adjustment of the secondary mirror is one of the key steps to ensure the performance of the system. This process requires precise control of the position and posture of the secondary mirror so that it forms a correct optical path with the primary mirror to meet the imaging requirements of the system. This article will elaborate on the specific steps before using the second hologram fixture (CGH2) to position the secondary mirror and adjust the position and posture of the secondary mirror by detecting the optical path. The following is a detailed description of the above steps:

[0104] Before positioning the secondary mirror, the position of the interferometer must be adjusted. After the interferometer is moved to the position of the primary mirror, ensure that it maintains an appropriate distance and angle with the primary mirror and the detection optical path. The purpose of this step is to use the spherical wave emitted by the interferometer to perform interference measurement with CGH2, so as to accurately determine the position and attitude of the secondary mirror. When moving the interferometer, its stability and accuracy must be ensured to avoid introducing additional errors. When adjusting the position of the interferometer, its relative position relationship with the primary mirror, CGH2 and the detection optical path must be considered to ensure the accuracy of the measurement results. Install the standard spherical lens that matches the CGH2 on the interferometer. The function of this standard spherical lens is to generate a spherical wave that matches the alignment area of ​​the CGH2 interferometer. During the installation process, ensure that the lens and the interferometer are accurately aligned to avoid any deviation or error. When selecting a standard spherical lens, ensure that its surface accuracy and focal length meet the measurement requirements. During the installation process, special tools and fixtures must be used to ensure the stability and accuracy of the lens.

[0105] The zero fringe state indicates that the spherical wave emitted by the interferometer perfectly matches the interferometer alignment area of ​​the CGH2. When adjusting the interferometer, pay close attention to the changes in the interference fringes to ensure the accuracy and stability of the adjustment process. Before positioning the secondary mirror, the entire detection optical path must be thoroughly cleaned and inspected to ensure that there are no dust, oil or other contaminants that affect the measurement results. Ensure the accuracy and stability of the fine-tuning mechanism to avoid damage to the secondary mirror or the introduction of additional errors during the adjustment process.

[0106] Based on the first embodiment and / or the second embodiment of the present application, in the third embodiment of the present application, the same or similar contents as those of the above-mentioned first and second embodiments can refer to the above introduction, and will not be repeated later. Figure 5 Step S30, the step of positioning the secondary mirror by using the second hologram inspection fixture, and adjusting the position and posture of the secondary mirror through the detection optical path so that the position of the secondary mirror and the primary mirror reaches the required level, comprises:

[0107] Step S31: keeping the position of the interferometer unchanged, placing the secondary mirror in the detection light path;

[0108] Step S32: a wavefront matching the surface phase of the secondary mirror is emitted from the secondary mirror detection area in the second hologram inspection fixture, is incident on the secondary mirror, and is then reflected back to the interferometer by the surface of the secondary mirror to generate the interference fringes;

[0109] Step S33: performing zero position detection on the surface shape of the secondary mirror, and adjusting the tilt and translation of the secondary mirror according to the detection result to determine the positional relationship between the secondary mirror and the second hologram inspection fixture;

[0110] Step S34: determining the positional relationship between the secondary mirror and the primary mirror according to the positional relationship between the secondary mirror and the second hologram gauge.

[0111] In this embodiment, the accurate positioning and adjustment of the secondary mirror in the process of assembling the off-axis primary and secondary mirror system is the key to ensuring the imaging quality of the system. This section will elaborate on how to use the second hologram fixture (CGH2) to position the secondary mirror, and adjust the position and posture of the secondary mirror by detecting the optical path, so that its position relationship with the primary mirror meets the design requirements. The following is a detailed description of the above steps:

[0112] Step S31: Place the secondary mirror in the detection light path. Carefully place the secondary mirror in the detection light path while keeping the interferometer position unchanged. Ensure that the placement position of the secondary mirror matches the preset adjustment position to avoid introducing unnecessary errors.

[0113] At this time, the secondary mirror should be in an adjustable state so that the position and attitude can be adjusted later through the fine-tuning mechanism. Ensure the cleanliness and stability of the secondary mirror to avoid contamination or damage during the installation and adjustment process.

[0114] Step S32: After the interferometer emits a spherical wave that passes through the secondary mirror detection area of ​​CGH2, it emits a wavefront that matches the phase of the secondary mirror surface. These wavefronts will be incident on the secondary mirror and reflected back to the interferometer by the surface of the secondary mirror. In the interferometer, the reflected wavefront will interfere with the reference wavefront emitted by the interferometer to form interference fringes. These interference fringes will be used for subsequent surface shape detection and secondary mirror positioning. When performing wavefront incidence and interference fringes generation, the position of CGH2 must be ensured to avoid introducing additional errors. Pay close attention to the changes in the interference fringes to ensure that they are clear, stable and easy to observe.

[0115] Step S33: Zero position detection and adjustment of secondary mirror surface shape. Use an interferometer to perform zero position detection on the surface shape of the secondary mirror. By observing the interferometer surface shape detection results, it can be determined whether the surface shape of the secondary mirror meets the design requirements, and the secondary mirror can be positioned at the same time. According to the detection results, the secondary mirror is adjusted to tilt and translate using a fine-tuning mechanism. By repeatedly adjusting and observing the changes in the interference fringes, the ideal secondary mirror position can be gradually approached. When performing secondary mirror surface shape detection, the accuracy and stability of the interferometer must be ensured to avoid introducing measurement errors. When adjusting the position and posture of the secondary mirror, pay close attention to the changes in the interference fringes to ensure the accuracy and stability of the adjustment process.

[0116] Step S34: Determine the positional relationship between the secondary mirror and the primary mirror. After completing the surface shape detection and position adjustment of the secondary mirror, the positional relationship between the secondary mirror and the primary mirror can be further determined according to the positional relationship between the secondary mirror and CGH2 (i.e., the positional relationship determined in step S33). This usually involves accurate measurement and adjustment of parameters such as the relative position, tilt angle and spacing between the secondary mirror and the primary mirror. When determining the positional relationship between the secondary mirror and the primary mirror, the accuracy and stability of the measurement process must be ensured. The influence of environmental factors (such as temperature, humidity, vibration, etc.) on the measurement results must be taken into account, and corresponding measures must be taken to compensate. If the measurement results do not meet the design requirements, it may be necessary to re-perform the surface shape detection and position adjustment of the secondary mirror, or to fine-tune the position and posture of the primary mirror. Through the detailed elaboration of the above steps S31 to S34, we understand how to use the second hologram inspection fixture (CGH2) to position the secondary mirror, and adjust the position and posture of the secondary mirror by detecting the optical path. This process involves the use of an interferometer, zero position detection of the secondary mirror surface shape, adjustment of the fine-tuning mechanism, and determination of the positional relationship between the secondary mirror and the primary mirror. Each step requires precise operation and close monitoring to ensure that the final system imaging quality meets the design requirements.

[0117] Other embodiments or specific implementation methods of the primary and secondary mirror adjustment device of the off-axis reflection system of the present application can refer to the above-mentioned method embodiments, which will not be repeated here.

[0118] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0119] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0120] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory / random access memory, a disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0121] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for adjusting primary and secondary mirrors of an off-axis system, characterized in that: The method for assembling and adjusting the primary and secondary mirrors of the off-axis reflection system comprises: According to the settings of the interferometer and the first hologram inspection fixture, the primary mirror is placed in the detection light path and the position is determined; According to the result of the position determination, placing a second hologram inspection fixture in the detection light path so that the second hologram inspection fixture is consistent with the positioning reference of the primary mirror; The secondary mirror is positioned by using the second hologram inspection fixture, and the position and posture of the secondary mirror are adjusted through the detection optical path so that the positions of the secondary mirror and the primary mirror meet the requirements.

2. The method according to claim 1, characterized in that Before the step of placing the primary mirror in the detection light path and determining the position according to the setting of the interferometer and the first hologram inspection fixture, the method includes: Installing a standard spherical lens matching the first hologram inspection fixture on the interferometer; The spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​the first hologram tester, and the first hologram tester is adjusted so that the interference fringes generated in the interferometer alignment area of ​​the first hologram tester reach a zero fringe state.

3. The method according to claim 2, characterized in that The step of placing the primary mirror in the detection light path and determining the position according to the setting of the interferometer and the first hologram inspection fixture comprises: Keeping the positions of the interferometer and the first hologram inspection fixture unchanged, placing the primary mirror in the detection light path; The primary mirror detection area of ​​the first hologram inspection fixture emits a wavefront that matches the surface phase of the primary mirror, which is incident on the primary mirror and then reflected back to the interferometer by the surface of the primary mirror to generate interference fringes; The surface shape of the primary mirror is subjected to zero position detection, and the inclination and translation of the primary mirror are adjusted according to the detection result to determine the positional relationship between the primary mirror and the first hologram inspection fixture.

4. The method according to claim 3, characterized in that The step of placing the second hologram inspection fixture in the detection light path according to the result of the position determination so that the second hologram inspection fixture is consistent with the positioning reference of the primary mirror comprises: The second hologram gauge is placed in the detection optical path, and the light emitted from the second hologram gauge alignment area on the first hologram gauge is incident on the first hologram gauge alignment area on the second hologram gauge, and returns to the interferometer along the original path through the second hologram gauge to generate the interference fringes; Finely adjusting the position of the second hologram inspection fixture so that the interference fringes reach a zero-fringe state; The positioning references of the second hologram inspection fixture and the primary mirror are made consistent.

5. The method according to claim 1, characterized in that Before the step of positioning the secondary mirror by using the second hologram inspection fixture and adjusting the position and posture of the secondary mirror through the detection optical path so that the position of the secondary mirror and the primary mirror reaches the required level, the method includes: Adjusting the position of the interferometer and moving the interferometer behind the position of the primary mirror; Mounting a standard spherical lens matching the second hologram inspection fixture on the interferometer so that the spherical wave emitted by the interferometer is incident on the interferometer alignment area of ​​the second hologram inspection fixture; The interferometer is adjusted so that the interference fringes generated by the interferometer aiming area reach a zero fringe state.

6. The method according to claim 4, characterized in that The step of positioning the secondary mirror by using the second hologram inspection fixture, and adjusting the position and posture of the secondary mirror by using the detection optical path so that the position of the secondary mirror and the primary mirror meet the requirements, comprises: Keeping the position of the interferometer unchanged, placing the secondary mirror in the detection light path; The wavefront emitted from the secondary mirror detection area in the second hologram inspection fixture and matching the surface phase of the secondary mirror is incident on the secondary mirror, and then reflected back to the interferometer by the surface of the secondary mirror to generate the interference fringes; Performing zero position detection on the surface shape of the secondary mirror, and adjusting the inclination and translation of the secondary mirror according to the detection result to determine the positional relationship between the secondary mirror and the second hologram inspection fixture; The positional relationship between the secondary mirror and the primary mirror is determined according to the positional relationship between the secondary mirror and the second hologram gauge.

7. The method according to claim 6, characterized in that The step of installing a standard spherical lens matching the first hologram inspection fixture on the interferometer further includes: Detecting the working state of the interferometer; When the working state of the interferometer is in a working state without fault indication, the step of installing the standard spherical lens matched with the first hologram gauge on the interferometer is performed.

8. A primary and secondary mirror adjustment device for an off-axis reflection system, characterized in that: The primary and secondary mirror adjustment device of the off-axis reflection system comprises: a primary mirror determination module, a second hologram inspection fixture determination module and a secondary mirror determination module; The primary mirror determination module places the primary mirror in the detection light path and determines the position according to the settings of the interferometer and the first hologram inspection fixture; The second hologram fixture determination module places the second hologram fixture in the detection light path according to the position determination result so that the second hologram fixture is consistent with the positioning reference of the primary mirror; The secondary mirror determination module uses the second hologram inspection fixture to position the secondary mirror, and adjusts the position and posture of the secondary mirror through the detection optical path so that the positions of the secondary mirror and the primary mirror meet the requirements.

9. A primary and secondary mirror adjustment device for an off-axis reflection system, characterized in that: The primary and secondary mirror adjustment device of the off-axis reflection system includes: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, the steps of the primary and secondary mirror adjustment method of the off-axis reflection system are implemented as described in any one of claims 1 to 7.

10. A computer storage medium, characterized in that: The computer storage medium stores a computer program, and when the computer program is executed by the processor, the steps of the method for adjusting the primary and secondary mirrors of the off-axis reflection system according to any one of claims 1 to 7 are implemented.

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